Question: $K$ is the midpoint of $\overline{JL}$ $J$ $K$ $L$ If: $ JK = 9x + 3$ and $ KL = 4x + 18$ Find $JL$.
Explanation: A midpoint divides a segment into two segments with equal lengths. ${JK} = {KL}$ Substitute in the expressions that were given for each length: $ {9x + 3} = {4x + 18}$ Solve for $x$ $ 5x = 15$ $ x = 3$ Substitute $3$ for $x$ in the expressions that were given for $JK$ and $KL$ $ JK = 9({3}) + 3$ $ KL = 4({3}) + 18$ $ JK = 27 + 3$ $ KL = 12 + 18$ $ JK = 30$ $ KL = 30$ To find the length $JL$ , add the lengths ${JK}$ and ${KL}$ $ JL = {JK} + {KL}$ $ JL = {30} + {30}$ $ JL = 60$